This invention relates to a tracking apparatus for a helical scan type video tape recorder.
The so-called autotracking apparatus has been introduced for the purpose of allowing video heads to accurately scan a recorded track.
An autotracking apparatus can provide a reproduced picture without noise bands in a specific mode reproduction, such as slow speed reproduction or still reproduction at a running speed which is different from the tape running speed used during the recording. Such autotracking apparatus is so constructed that the usual video signal reproducing video heads are mounted on a movable unit having electro-mechanical conversion elements; a search signal (e.g. a sine-wave signal) which is used as drive signal is supplied to the electro-mechanical conversion elements, and the position of said video head with respect to the recorded track is determined from the search signal and a reproduction envelope of the video heads, so that a control loop is arranged to keep video heads on track.
In a case where the tracking apparatus of the above-noted system uses a plurality of video heads, each video head is controllable as above, on a basis of its reproduction envelope. Hence, it is impossible to determine if the video head has scanned a desired track or an adjacent track, thereby creating the problem of producing the so-called "track jumping".